Medical research

Nitisinone increases melanin in people with albinism

A small pilot clinical study at the National Eye Institute (NEI) suggests that the drug nitisinone increases melanin production in some people with oculocutaneous albinism type 1B (OCA-1B), a rare genetic disease that causes ...

Cardiology

Novel technique accurately assesses cardiovascular risks

A new noninvasive technique for imaging the carotid artery offers advantages over other imaging methods and could provide an earlier, more accurate assessment of cardiovascular disease risk, according to a study published ...

Medical research

Mouse and human skin cells produce melanin on a 48-hour cycle

Researchers have discovered that mouse skin and skin cells from humans produce pigmentation in response to sunlight on a 48-hour cycle. They observed that exposing skin to ultraviolet light every 2 days yielded darker pigmentation ...

Diseases, Conditions, Syndromes

Vitiligo treated successfully with arthritis drug and light therapy

Building on prior research that examined the use of an arthritis medication to treat vitiligo, a team of Yale dermatologists has successfully applied a novel combination therapy—the medication and light—to restore skin ...

Medical research

Research team lays bare melanin's DNA guarding mechanism

With a little help from chickens and video cameras, scientists have captured live the moment when skin gets darker. In a study appearing in Scientific Reports, a Japanese team has filmed and demystified the process by which ...

Medical research

Sunlight continues to damage skin in the dark

Much of the damage that ultraviolet radiation (UV) does to skin occurs hours after sun exposure, a team of Yale-led researchers concluded in a study that was published online Feb. 19 by the journal Science.

page 1 from 4

Melanin

Melanin i/ˈmɛlənɪn/ (Greek: μέλας, black) is a pigment that is ubiquitous in nature, being found in most organisms (spiders are one of the few groups in which it has not been detected). In animals melanin pigments are derivatives of the amino acid tyrosine. The most common form of biological melanin is eumelanin, a brown-black polymer of dihydroxyindole carboxylic acids, and their reduced forms. All melanins can be considered as derivatives of polyacetylene, since they rely on a polyconiugate structure. Another common form of melanin is pheomelanin, a red-brown polymer of benzothiazine units largely responsible for red hair and freckles. The presence of melanin in the archaea and bacteria kingdoms is an issue of ongoing debate among researchers in the field.

The increased production of melanin in human skin is called melanogenesis. Production of melanin is stimulated by DNA damage induced by UVB-radiation, and it leads to a delayed development of a tan. This melanogenesis-based tan takes more time to develop, but it is long-lasting.

The photochemical properties of melanin make it an excellent photoprotectant. It absorbs harmful UV-radiation (ultraviolet) and transforms the energy into harmless heat through a process called "ultrafast internal conversion". This property enables melanin to dissipate more than 99.9% of the absorbed UV radiation as heat (see photoprotection). This prevents the indirect DNA damage that is responsible for the formation of malignant melanoma and other skin cancers.

This text uses material from Wikipedia, licensed under CC BY-SA